ECFS standards of care on CFTR-related disorders: Identification and care of the disorders.

This is the third paper in the series providing updated information and recommendations for people with cystic fibrosis transmembrane conductance regulator (CFTR)-related disorder (CFTR-RD). This paper covers the individual disorders, including the established conditions - congenital absence of the vas deferens (CAVD), diffuse bronchiectasis and chronic or acute recurrent pancreatitis - and also other conditions which might be considered a CFTR-RD, including allergic bronchopulmonary aspergillosis, chronic rhinosinusitis, primary sclerosing cholangitis and aquagenic wrinkling. The CFTR functional and genetic evidence in support of the condition being a CFTR-RD are discussed and guidance for reaching the diagnosis, including alternative conditions to consider and management recommendations, is provided. Gaps in our knowledge, particularly of the emerging conditions, and future areas of research, including the role of CFTR modulators, are highlighted.

Enzymatic tissue processing after testicular biopsy in non-obstructive azoospermia enhances sperm retrieval.

STUDY QUESTION: What is the added value of enzymatic processing of testicular biopsies on testicular sperm retrieval (SR) rates for patients with non-obstructive azoospermia (NOA)? SUMMARY ANSWER: In addition to mechanical mincing, enzymatic digestion increased SR rates in testicular biopsies of NOA patients. WHAT IS KNOWN ALREADY: Many studies focus on the surgical approach to optimize recovery of testicular sperm in NOA, and in spite of that, controversy still exists about whether the type of surgery makes any difference as long as multiple biopsies are taken. Few studies, however, focus on the role of the IVF laboratory and the benefit of additional lab procedures, e.g. enzymatic digestion, in order to optimize SR rates. STUDY DESIGN SIZE DURATION: This retrospective single-center cohort study included all patients who underwent their first testicular sperm extraction (TESE) by open multiple-biopsy method between January 2004 and July 2022. Only patients with a normal karyotype, absence of Y-q deletions and a diagnosis of NOA based on histology were included. The primary outcome was SR rate after mincing and/or enzymes. The secondary outcome was cumulative live birth (CLB) after ICSI with fresh TESE and subsequent ICSI cycles with frozen TESE. PARTICIPANTS/MATERIALS SETTING METHODS: Multiple biopsies were obtained from the testis, unilaterally or bilaterally, on the day of oocyte retrieval. Upon mechanical mincing, biopsies were investigated for 30 min; when no or insufficient numbers of spermatozoa were observed, enzymatic treatment was performed using Collagenase type IV. Multivariable regression analysis was performed to predict CLB per TESE by adjusting for the following confounding factors: male FSH level, female age, and requirement of enzymatic digestion to find sperm. MAIN RESULTS AND THE ROLE OF CHANCE: We included 118 patients, of whom 72 (61.0%) had successful SR eventually. Spermatozoa were retrieved after mechanical mincing for 28 patients (23.7%; 28/118) or after additional enzymatic digestion for another 44 patients (37.2%; 44/118). Thus, of the 90 patients requiring enzymatic digestion, sperm were retrieved for 44 (48.9%). Male characteristics were not different between patients with SR after mincing or enzymatic digestion, in regard to mean age (34.5 vs 34.5 years), testis volume (10.2 vs 10.6 ml), FSH (17.8 vs 16.9 IU/l), cryptorchidism (21.4 vs 34.1%), varicocele (3.6 vs 4.6%), or histological diagnosis (Sertoli-cell only 53.6 vs 47.7%, maturation arrest 21.4 vs 38.6%, sclerosis/atrophy 25.0 vs 13.6%).Of the 72 patients with sperm available for ICSI, 23/72 (31.9%) achieved a live birth (LB) after the injection with fresh testicular sperm (and fresh or frozen embryo transfers). Of the remaining 49 patients without LB, 34 (69.4%) had supernumerary testicular sperm frozen. Of these 34 patients, 19 (55.9%) continued ICSI with frozen testicular sperm, and 9/19 (47.4%) had achieved an LB after ICSI with frozen testicular sperm. Thus, the total CLB was 32/118 (27.1%) per TESE or 32/72 (44.4%) per TESE with sperm retrieved.Of the female characteristics (couples with sperm available), only female age (30.3 vs 32.7 years; P = 0.042) was significantly lower in the group with a LB, compared to those without.The CLB with testicular sperm obtained after enzymatic digestion was 31.8% (14/44), while the CLB with sperm obtained after mincing alone was 64.3% (18/28). Multivariable logistic regression analysis showed that when enzymatic digestion was required, it was associated with a significant decrease in CLB per TESE (OR: 0.23 (0.08-0.7); P = 0.01). LIMITATIONS REASONS FOR CAUTION: Limitations of the study are related to the retrospective design. However, the selection of only patients with NOA, and specific characteristics (normal karyotype and absence Y-q deletion) and having their first TESE, strengthens our findings. WIDER IMPLICATIONS OF THE FINDINGS: Enzymatic processing increases the SR rate from testicular biopsies of NOA patients compared to mechanical mincing only, demonstrating the importance of an appropriate laboratory protocol. However, NOA patients should be counseled that when sperm have been found after enzymatic digestion, their chances to father a genetically own child may be lower compared to those not requiring enzymatic digestion. STUDY FUNDING/COMPETING INTERESTS: None reported. TRIAL REGISTRATION NUMBER: N/A.

Spermatogenesis after gonadotoxic childhood treatment: follow-up of 12 patients.

STUDY QUESTION: What is the long-term impact of presumed gonadotoxic treatment during childhood on the patient's testicular function at adulthood? SUMMARY ANSWER: Although most patients showed low testicular volumes and some degree of reproductive hormone disruption 12.3 (2.3-21.0) years after gonadotoxic childhood therapy, active spermatogenesis was demonstrated in the semen sample of 8 out of the 12 patients. WHAT IS KNOWN ALREADY: In recent decades, experimental testicular tissue banking programmes have been set up to safeguard the future fertility of young boys requiring chemo- and/or radiotherapy with significant gonadotoxicity. Although the risk of azoospermia following such therapies is estimated to be high, only limited long-term data are available on the reproductive potential at adulthood. STUDY DESIGN SIZE DURATION: This single-centre prospective cohort study was conducted between September 2020 and February 2023 and involved 12 adult patients. PARTICIPANTS/MATERIALS SETTING METHODS: This study was carried out in a tertiary care centre and included 12 young adults (18.1-28.3 years old) who had been offered testicular tissue banking prior to gonadotoxic treatment during childhood. All patients had a consultation and physical examination with a fertility specialist, a scrotal ultrasound to measure the testicular volumes and evaluate the testicular parenchyma, a blood test for assessment of reproductive hormones, and a semen analysis. MAIN RESULTS AND THE ROLE OF CHANCE: Testicular tissue was banked prior to the gonadotoxic treatment for 10 out of the 12 included patients. Testicular volumes were low for 9 patients, and 10 patients showed some degree of reproductive hormone disruption. Remarkably, ongoing spermatogenesis was demonstrated in 8 patients at a median 12.3 (range 2.3-21.0) years post-treatment. LIMITATIONS REASONS FOR CAUTION: This study had a limited sample size, making additional research with a larger study population necessary to verify these preliminary findings. WIDER IMPLICATIONS OF THE FINDINGS: These findings highlight the need for multicentric research with a larger study population to establish universal inclusion criteria for immature testicular tissue banking. STUDY FUNDING/COMPETING INTERESTS: This study was conducted with financial support from the Research Programme of the Research Foundation-Flanders (G010918N), Kom Op Tegen Kanker, and Scientific Fund Willy Gepts (WFWG19-03). The authors declare no competing interests. TRIAL REGISTRATION NUMBER: NCT04202094; https://clinicaltrials.gov/ct2/show/NCT04202094?id=NCT04202094&draw=2&rank=1 This study was registered on 6 December 2019, and the first patient was enrolled on 8 September 2020.

Pregnancy after vasectomy: surgical reversal or assisted reproduction?

STUDY QUESTION: Should we opt for surgical vasovasostomy or IVF/ICSI after a vasectomy? SUMMARY ANSWER: Both options reveal acceptable pregnancy rates though the time to pregnancy was significantly lower in the immediate IVF/ICSI group. WHAT IS KNOWN ALREADY: About 7.4% of men regret their vasectomy and express a renewed child wish. The choice between surgical vasectomy reversal or ICSI remains difficult for patients and their fertility specialist. STUDY DESIGN, SIZE, DURATION: This study was a retrospective single-center cohort analysis of all males with a vasectomy in the past seeking treatment between 2006 and 2011 (n = 163). One group of patients opted for a reanastomosis procedure while the others opted for an immediate IVF/ICSI treatment. This included 99 males who underwent reanastomosis and 64 couples who immediately underwent ICSI treatment. PARTICIPANTS/MATERIALS, SETTING, METHODS: All reanastomosis procedures were done by the same surgeon. ICSI was used in all cases where testicular sperm were extracted by fine needle aspiration (FNA) or testicular sperm extraction (TESE). MAIN RESULTS AND THE ROLE OF CHANCE: The mean male age at vasectomy was 35.5 years and 44.4 years at reanastomosis. The mean (range) obstructive interval was 9.53 years (1-27). No significant differences were found between the two groups in female patient characteristics, such as age and parity. In the reversal group, the crude cumulative delivery rate (CDR) was 49.5%. However, in the 45 patients of this group who attempted to conceive spontaneously ('primary reanastomosis' pathway), the crude CDR was 40.0%. The remaining 54 patients (the 'switchers' pathway) who underwent a reversal procedure and later switched to ART, had a crude CDR of 57.4%. Of these, four patients opted for insemination, including two who later decided to switch to IVF/ICSI. The 64 patients who immediately underwent IVF/ICSI ('primary IVF/ICSI' pathway) had a crude CDR of 43.8% and an expected CDR of 51.6%. The difference in delivery rates between the primary reanastomosis group (40.0%) and the primary IVF/ICSI group (43.8%) was not statistically significant. Time to pregnancy was significantly shorter in the primary IVF/ICSI pathway, at 8.2 versus 16.3 months in the reanastomosis group. LIMITATIONS, REASONS FOR CAUTION: The study population was rather small. Furthermore, the study may be limited by the fact that the reason for the renewed child wish in most cases was a new relationship with another woman, a factor which may also play a role in the cause of infertility. WIDER IMPLICATIONS OF THE FINDINGS: Recanalisation of the vas seems to be a reasonable alternative for patients who do not wish to undergo immediate IVF/ICSI. In those who opt for ART immediately, the cumulative pregnancy rates seem comparable but the pregnancies occurred earlier. STUDY FUNDING, COMPETING INTEREST(S): No funding was used for this study. There is no conflict of interest for this study. TRIAL REGISTRATION NUMBER: N/A.

When does germ cell loss and fibrosis occur in patients with Klinefelter syndrome?

STUDY QUESTION: When does germ cell loss and fibrosis occur in patients with Klinefelter syndrome (KS)? SUMMARY ANSWER: In KS, germ cell loss is not observed in testicular tissue from fetuses in the second semester of pregnancy but present at a prepubertal age when the testicular architecture is still normal, while fibrosis is highly present at an adolescent age. WHAT IS KNOWN ALREADY: Most KS patients are azoospermic at adult age because of a massive germ cell loss. However, the timing when this germ cell loss starts is not known. It is assumed that germ cell loss increases at puberty. Therefore, testicular sperm extraction (TESE) at an adolescent age has been suggested to increase the chances of sperm retrieval at onset of spermatogenesis. However, recent data indicate that testicular biopsies from peripubertal KS patients contain only a few germ cells. STUDY DESIGN, SIZE, DURATION: In this study, we give an update on fertility preservation in adolescent KS patients and evaluate whether fertility preservation would be beneficial at prepubertal age. The possibility of retrieving testicular spermatozoa by TESE was evaluated in adolescent and adult KS men. The presence of spermatogonia and the degree of fibrosis were also analysed in testicular biopsies from KS patients at different ages. The patients were divided into four age groups: foetal (n = 5), prepubertal (aged 4-7 years; n = 4), peripubertal (aged 12-16 years; n = 20) and adult (aged 18-41 years; n = 27) KS patients. PARTICIPANTS/MATERIALS, SETTING, METHODS: In peripubertal and adult KS patients, retrieval of spermatozoa was attempted by semen analysis after masturbation, vibrostimulation, electroejaculation or by TESE. MAGE-A4 immunohistochemistry was performed to evaluate the presence of germ cells in testicular biopsies from foetal, prepubertal, peripubertal and adult KS patients. Tissue morphology was evaluated by haematoxylin-periodic acid Schiff (H/PAS) staining. MAIN RESULTS AND THE ROLE OF CHANCE: Testicular spermatozoa were collected by TESE in 48.1% of the adult KS patients, while spermatozoa were recovered after TESE in only one peripubertal patient (5.0%). Germ cells were detectable in testicular biopsies from 21% of adult men for whom no spermatozoa could be retrieved by TESE and in 31.5% of peripubertal KS boys. Very small numbers of spermatogonia (0.03-0.06 spermatogonia/tubule) were detected in three out of four (75%) prepubertal patients. At a foetal age, the number of germ cells was similar for KS and control samples. Increased signs of fibrosis were not present at foetal and prepubertal ages, but peripubertal and adult KS patients showed high levels of fibrosis. LARGE SCALE DATA: N/A. LIMITATIONS, REASONS FOR CAUTION: Only four prepubertal biopsies were included in this study, but they all showed a very low germ cell number. A high variability in the number of spermatogonia per mm2 was observed in the limited (n = 5) number of foetal biopsies. However, testicular biopsies from prepubertal and foetal Klinefelter patients are difficult to obtain. WIDER IMPLICATIONS OF THE FINDINGS: Testicular tissue banking at a prepubertal age has been suggested as a potential method for fertility preservation in early diagnosed KS boys. However, our results show that a reduction in germ cell number has already taken place in childhood. Therefore, offering testicular tissue banking in young KS boys to prevent subsequent sterility might be a questionable strategy. However, this should be confirmed in a larger study population. STUDY FUNDING/COMPETING INTEREST(S): This project was funded by the scientific Fund Willy Gepts from the UZ Brussel (D.V.S., J.D.S.), grants from the Vrije Universiteit Brussel (E.G.) and a Methusalem grant (K.S.). D.V.S is a post-doctoral fellow of the Fonds Wetenschappelijk Onderzoek (FWO; 12M2815N). No conflict of interest is declared.

Chromosomal abnormalities in 1663 infertile men with azoospermia: the clinical consequences.

STUDY QUESTION: What is the prevalence of chromosomal abnormalities in azoospermic men and what are the clinical consequences in terms of increased risk for absent spermatogenesis, miscarriages and offspring with congenital malformations? SUMMARY ANSWER: The prevalence of chromosomal abnormalities in azoospermia was 14.4%, and the number of azoospermic men needed to be screened (NNS) to identify one man with a chromosomal abnormality with increased risk for absence of spermatogenesis was 72, to prevent one miscarriage 370-739 and to prevent one child with congenital malformations 4751-23 757. WHAT IS KNOWN ALREADY: Infertility guidelines worldwide advise screening of non-iatrogenic azoospermic men for chromosomal abnormalities, but only few data are available on the clinical consequences of this screening strategy. STUDY DESIGN, SIZE, DURATION: This retrospective multicentre cross-sectional study of non-iatrogenic azoospermic men was performed at the University Hospital Brussels, Belgium, and the University Medical Centre Groningen, The Netherlands, between January 2000 and July 2016. PARTICIPANTS/MATERIALS, SETTING, METHODS: Analysis of clinical registries retrospectively identified 1663 non-iatrogenic azoospermic men with available results of karyotyping and FSH serum levels. Iatrogenic azoospermia was an exclusion criterion, defined as azoospermia after spermatotoxic medical treatment, exogenous androgen suppletion or vasectomy and/or vasovasostomy. Also, men with a clinical diagnosis of anejaculation or hypogonadotropic hypo-androgenism and/or FSH values <1.0 U/l were excluded. Chromosomal abnormalities were categorized according to their (theoretical) impact on clinical consequences for the patient (i.e. an increased risk for absence of spermatogenesis) and adverse pregnancy outcomes (i.e. miscarriage or offspring with congenital malformations), in both normogonadotropic (FSH < 10 U/l) and hypergonadotropic (FSH ≥ 10 U/l) azoospermia. We estimated the NNS for chromosomal abnormalities to identify one man with absence of spermatogenesis and to prevent one miscarriage or one child with congenital malformations, and calculated the surgical sperm retrieval rates per chromosomal abnormality. MAIN RESULTS AND THE ROLE OF CHANCE: The overall prevalence of chromosomal abnormalities in azoospermia was 14.4% (95% CI 12.7-16.1%), its prevalence being higher in hypergonadotropic azoospermia (20.2%, 95% CI 17.8-22.7%) compared to normogonadotropic azoospermia (4.9%, 95% CI 3.2-6.6%, P < 0.001). Klinefelter syndrome accounted for 83% (95% CI 77-87%) of abnormalities in hypergonadotropic azoospermia. The NNS to identify one man with increased risk for absence of spermatogenesis was 72, to prevent one miscarriage 370-739, and to prevent one child with congenital malformations 4751-23 757. There was no clinically significant difference in NNS between men with normogonadotropic and hypergonadotropic azoospermia. The surgical sperm retrieval rate was significantly higher in azoospermic men with a normal karyotype (60%, 95% CI 57.7-63.1%) compared to men with a chromosomal abnormality (32%, 95% CI 25.9-39.0%, P < 0.001). The sperm retrieval rate in Klinefelter syndrome was 28% (95% CI 20.7-35.0%). LIMITATIONS, REASONS FOR CAUTION: The absolute number of chromosomal abnormalities associated with clinical consequences and adverse pregnancy outcomes in our study was limited, thereby increasing the role of chance. Further, as there are currently no large series on outcomes of pregnancies in men with chromosomal abnormalities, our conclusions are partly based on assumptions derived from the literature. WIDER IMPLICATIONS OF THE FINDINGS: The NNS found can be used in future cost-effectiveness studies and the evaluation of current guidelines on karyotyping in non-iatrogenic azoospermia. STUDY FUNDING/COMPETING INTEREST(S): None to declare.

Are AZFb deletions always incompatible with sperm production?

Deletions on the long arm of the Y chromosome are a well-known cause of male infertility and it is generally accepted that deletions involving the AZFb region are not compatible with sperm production. Here, we report on two patients for whom basic diagnostic tests showed a deletion of the AZFb region. Unexpectedly, both patients had some residual sperm production. Subsequently, extension and additional analyses of the AZFb region disclosed an aberrant deletion pattern. Therefore, these results emphasize the need for a detailed and powerful analysis of cases where first-line Yq deletion tests reveal an AZFb deletion. Moreover, our study clearly demonstrated that only a very careful selection of test markers will avoid the pitfall of a 'no further treatment possible' wrongful conclusion.

Vitrified-warmed blastocyst transfer on the 5th or 7th day of progesterone supplementation in an artificial cycle: a randomised controlled trial.

Prospective studies comparing different durations of progesterone supplementation before transfer of vitrified-warmed blastocysts in an artificial cycle are lacking. However, in oocyte donation programmes, the sporadic available evidence demonstrates considerable differences in clinical pregnancy rates according to the duration of progesterone administration. This randomised controlled trial (RCT), included 303 patients undergoing a frozen-thawed embryo transfer (FET) of one or two vitrified-warmed blastocyst(s) in an artificial cycle. Randomisation was performed when the endometrial thickness reached ≥7 mm after oestrogen supplementation. One hundred and fifty two patients in group A received 7 d of vaginal micronised progesterone tablets and 151 patients in group B received 5 d of micronised vaginal progesterone before FET. No differences were seen in clinical pregnancy rate between both groups: 42/152 (27.6%) in group A versus 49/151 (32.5%) in group B. Although no statistically significant difference was observed in clinical pregnancy rates, our study was powered to detect an absolute difference of 16%. In this regard, we cannot exclude that smaller, clinically relevant differences might exist and our study did not have the power to detect this. Patients were also not blinded for the intervention, causing a potential bias.

How successful is TESE-ICSI in couples with non-obstructive azoospermia?

STUDY QUESTION: What are the chances of a couple with infertility due to non-obstructive azoospermia (NOA) having their genetically own child by testicular sperm extraction combined with ICSI (TESE-ICSI)? SUMMARY ANSWER: Candidate TESE-ICSI patients with NOA should be counselled that, when followed-up longitudinally, only a minority (13.4%) of men embarking for TESE eventually become a biological father. WHAT IS KNOWN ALREADY: Data available in the literature are only fragmentary because they report either on sperm retrieval rates after TESE or on the outcome of ICSI once testicular spermatozoa has been obtained, mostly in a selected subpopulation. Unfortunately, reliable data to counsel men with NOA on their chance to become a biological father are still lacking. STUDY DESIGN, SIZE, DURATION: This is a retrospective cohort study performed in the Centre for Reproductive Medicine, University Hospital of Brussel, approved by the institutional review board of the hospital. PARTICIPANTS/MATERIALS, SETTING AND METHODS: We identified all patients with NOA, based on histology, who had their first testicular biopsy between 1994 and 2009. Patients were followed longitudinally during consecutive ICSI cycles with testicular sperm. The primary outcome measure was live birth delivery. The cumulative live birth delivery rate was calculated, based only on ICSI cycles with testicular sperm (fresh and/or frozen) available for injection. When patients delivered after transfer of supernumerary frozen embryos, this delivery was tallied up to the (unsuccessful) original fresh ICSI cycle. The sperm retrieval rate and pregnancy rate were secondary outcome measures. MAIN RESULTS AND THE ROLE OF CHANCE: Among the 714 men with NOA, 40.5% had successful sperm retrieval at their first TESE. In total, 261 couples had 444 ICSI cycles and 48 frozen embryo transfer cycles, leading to 129 pregnancies and 96 live birth deliveries. Crude and expected cumulative delivery rates after six ICSI cycles were 37 and 78%. LIMITATIONS AND REASON FOR CAUTION: A retrospective cohort study design was the only way to study the cumulative delivery rate after TESE-ICSI in couples with NOA. Intrinsic limitations are related to the observational study design. WIDER IMPLICATION OF THE FINDING: TESE-ICSI is a breakthrough in the treatment of infertility due to NOA, with almost 4 out of 10 (37%) couples having ICSI obtaining a delivery. However, unselected candidate NOA patients should be counselled, before undergoing TESE, that only one out of seven men (13.4%) eventually father their genetically own child. STUDY FUNDING AND COMPETING INTERESTS: None declared.

Administration of corifollitropin alfa on Day 2 versus Day 4 of the cycle in a GnRH antagonist protocol: a randomized controlled pilot study.

STUDY QUESTION: Does the initiation of corifollitropin alfa administration on cycle day 4 instead of cycle day 2 result in a reduced total rFSH consumption in a GnRH antagonist protocol? SUMMARY ANSWER: Initiation of corifollitropin alfa on cycle day 4 compared with day 2 results in significantly reduced total rFSH consumption at the end of the follicular phase. WHAT IS KNOWN ALREADY: In vitro fertilization treatment is associated with significant physical, psychological and emotional stress in infertile patients. This notion has fuelled the search for simplified treatment approaches that may reduce the treatment burden. The introduction of corifollitropin alfa has provided a more patient-friendly treatment protocol because it obviates the need for daily hormonal injections. In addition, postponing the initiation of hormonal stimulation should also reduce the total gonadotrophin consumption and the number of injections needed. STUDY DESIGN, SIZE, DURATION: A prospective randomized controlled pilot study was conducted in a university centre in Belgium. Between December 2011 and March 2013, 59 patients were randomized in the study and 52 of these patients received the allocated intervention. PARTICIPANTS/MATERIALS, SETTING, METHODS: All patients were randomly assigned to the control group (CD2), with initiation of corifollitropin alfa on cycle day 2, or to the study group (CD4) with initiation of stimulation on day 4. The GnRH antagonist was administered from cycle day 7 onwards in both treatment arms. The main outcome measure was the total rFSH consumption at the end of the follicular phase after corifollitropin alfa treatment. MAIN RESULTS AND THE ROLE OF CHANCE: The total dose of rFSH at the end of the follicular phase was significantly reduced in the CD4 group compared with the CD2 group (324 (276) IU in the CD2 group versus 173 (255) IU in the CD4 group, P = 0.015, mean difference -151, 95% confidence interval (CI) -301 to -1). A significant reduction of total duration of rFSH stimulation in the CD4 group was also observed (8.6 (1.4) days in CD2 group versus 7.8 (1.2) days in the CD4 group, P = 0.008, mean difference -0.8, 95% CI -1.6 to -0.1). The number of cumulus-oocyte-complexes was comparable in both treatment groups (12.8 (7.3) in CD2 group versus 14.7 (8.8) in the CD4 group, P = 0.461, mean difference 1.8, 95% CI -2.7 to 6.4). Ongoing pregnancy rates of 48% in the CD2 group and 41% in the CD4 group were achieved (P = 0.60, relative risk (RR) 0.85, 95% CI 0.46-1.56). Final oocyte maturation was triggered with GnRH agonist instead of hCG in two patients in the CD2 group and in eight patients in the CD4 group, because of an increased risk of ovarian hyperstimulation syndrome (P = 0.078, RR 3.7 (95% CI 0.88-15.8). LIMITATIONS, REASONS FOR CAUTION: Before general implementation can be advised, this trial should be validated in a much larger randomized trial. WIDER IMPLICATIONS OF THE FINDINGS If the approach of starting ovarian stimulation on Day 4 of the cycle could be implemented in a large population of infertile patients, it would result in a significant reduction of gonadotrophin consumption. STUDY FUNDING/COMPETING INTEREST(S): No external finance was involved in this study. C.B and N.P.P. have received fees from MSD. Otherwise the authors declare no conflict of interest regarding this study. TRIAL REGISTRATION NUMBER: The trial was registered at clinicaltrials.gov (NCT01633580).

Addition of highly purified HMG after corifollitropin alfa in antagonist-treated poor ovarian responders: a pilot study.

STUDY QUESTION: Will sequential administration of highly purified (hp)-HMG after corifollitropin alfa in a GnRH antagonist protocol benefit women with poor ovarian response according to the Bologna criteria? SUMMARY ANSWER: Corifollitropin alfa followed by hp-HMG in a GnRH antagonist protocol results in very promising pregnancy rates, albeit only in young (<40 years old) poor ovarian responders fulfilling the Bologna criteria. WHAT IS KNOWN ALREADY: Poor ovarian responders fulfilling the Bologna criteria have a very poor prognosis in terms of successful IVF outcome. Although a recent study demonstrated low pregnancy rates in this group of patients after treatment with corifollitropin alfa followed by recombinant FSH in a GnRH antagonist protocol, previous studies showed that the addition of LH activity in 36- to 39-year-old women significantly increases implantation rates. STUDY DESIGN, SIZE, DURATION: In this retrospective pilot study, we included poor ovarian responders fulfilling the Bologna criteria treated with a completely novel protocol, with corifollitropin alfa followed by hp-HMG in a GnRH antagonist setting. Overall, 51 patients were treated within a period of 1 year (August 2011-August 2012). PARTICIPANTS/MATERIALS, SETTING, METHODS: Patients received 150 µg corifollitropin alfa on second day of the menstrual cycle followed by a fixed daily dose of 0.25 mg of GnRH antagonist on Day 7 of the cycle onwards. On the ninth day of the cycle, a daily fixed dose of 300 IU hp-HMG was administered until the day of ovulation triggering. The primary outcome was ongoing pregnancy rate per patient. MAIN RESULTS AND THE ROLE OF CHANCE: Among 47 eligible women, 29 patients were <40 years old and 18 patients were ≥ 40 years old. No differences were observed in endocrine profile, number of cycles with oocyte retrieval (66 versus 67%) and cycles with embryo transfer (62 versus 61%) in women <40 versus ≥ 40 years old, respectively. However, 8 of the 29 women <40 years old had an ongoing pregnancy (28%) compared with 0 of 18 patients who were ≥ 40 years of age (P = 0.017). LIMITATIONS, REASONS FOR CAUTION: Owing to the specific retrospective study design, bias cannot be ruled out and these results should not be extrapolated to other treatment protocols for poor ovarian responders. Therefore, caution should be taken when interpreting the results. WIDER IMPLICATIONS OF THE FINDINGS: The promising results from this pilot study of corifollitropin alfa followed by hp-HMG stimulation indicate a potential beneficial effect in young poor ovarian responders fulfilling the Bologna criteria. The data provide the rationale for performing a randomized controlled trial to determine if there is sound evidence for a clinical introduction of this protocol. STUDY FUNDING/COMPETING INTEREST(S): No conflicts of interest to declare. No specific funding was received for this study.

Live birth rates following natural cycle IVF in women with poor ovarian response according to the Bologna criteria.

STUDY QUESTION: What is the effect of natural cycle IVF in women with poor ovarian response according to the new ESHRE definition for poor ovarian responders: the Bologna criteria? SUMMARY ANSWER: Although natural cycle IVF is a promising treatment option for normal responders, poor ovarian responders, as described by the Bologna criteria, have a very poor prognosis and do not appear to experience substantial benefits with natural cycle IVF. WHAT IS KNOWN ALREADY: Previous trials have shown that natural cycle IVF is an effective treatment for the general infertile population and might be an option for poor ovarian responders. However, none of the trials have examined the effect of natural cycle IVF in poor responders according to the Bologna criteria, the newly introduced definition by the ESHRE Working Group on Poor Ovarian Response Definition. In this trial, we examined the effect of natural cycle IVF in poor ovarian responders fulfilling the Bologna criteria. STUDY DESIGN, SIZE, DURATION: In this retrospective cohort trial, 164 consecutive patients, undergoing 469 natural cycle IVFs between 2008 and 2011 were included. Patients were stratified as poor and normal responders: 136 (390 cycles) were poor ovarian responders according to the Bologna criteria, whereas 28 women (79 treatment cycles) did not fulfil the criteria and were considered as normal responders. PARTICIPANTS/MATERIALS, SETTING, METHODS: All patients were monitored with hormonal analysis and ultrasound scan every second day, from Day 7 or 8 of the cycle onwards. When a follicle of >16 mm was observed, ovulation was triggered with 5000 IU of i.m. hCG and oocyte retrieval was performed 32 h later. MAIN RESULTS AND THE ROLE OF CHANCE: Live birth rates in poor responders according to the Bologna criteria were significantly lower compared with the control group of women; the live birth rate per cycle was 2.6 versus 8.9%, P = 0.006 and the live birth rate per treated patient was 7.4 versus 25%, P = 0.005. In poor responders according to the Bologna criteria, live birth rates were consistently low and did not differ among different age groups (≤ 35 years, 36-39 years and ≥ 40 years), with a range from 6.8 to 7.9%. LIMITATIONS, REASONS FOR CAUTION: A limitation of our analysis is its retrospective design; however, taking into account that we included only consecutive patients treated with exactly the same protocol, the likelihood of selection bias might be considerably limited. In addition, the control group in our study refers to women of younger age and therefore the promising results among patients who did not fulfil the Bologna criteria apply only to women of younger age. WIDER IMPLICATIONS OF THE FINDINGS: Our trial suggests that although natural cycle IVF is a promising treatment option for younger normal responders, its potential is very limited to poor ovarian responders as described by the Bologna criteria, irrespective of patient's age. This highlights the very poor prognosis of these women and therefore the urgent need for future trials to examine the effect of ovarian stimulation protocols in women with poor ovarian response as described by the Bologna criteria. STUDY FUNDING/COMPETING INTEREST(S): No funding was used. There are no competing interests to declare.